2 cups red wine vinegar
1 red onion, thinly sliced
1 pound skirt steak
1 clove garlic, halved
salt and pepper
2 Tbsp olive oil
12 fresh corn tortillas
1 avocado, pitted and sliced
1 cup fresh tomato salsa or fresh tomatillo sauce
Cilantro for garnish
1. Put the red onion in a small bowl and pour in enough red wine vinegar to cover well. Set aside for at least 30 minutes.
2. Cut the skirt steak into 4 equal pieces. Using a meat mallet, pound the beef to 1/4-inch thickness. If using an outdoor grill, preheat it now. Rub the cut side of the garlic clove all over the meat and season generously with salt and pepper. About 5 minutes before grilling, squeeze the juice of 1 lime over both sides of the beef.
3. Brush grill with olive oil and set the heat to high. Grill beef for 4 minutes per side. Remove from heat and let it rest for 5 minutes before chopping into 1/2 inch pieces.
4. Place four of the tortillas on a plate and sandwich them between dampened sheets of paper towel. Microwave for 45 seconds. Place warm tortillas in a towel-lined basket and cover. Repeat with remaining tortillas.
5. To assemble the tacos, place heaping spoonful of grilled steak onto the center of a tortilla. Top with marinated onions and a slice of avocado. Serve accompanies by tomato salsa or tomatillo sauce. Cut the remaining lime into wedges. Garnish with lime wedge and cilantro, if desired.
From Simply Mexican by Lourdes Castro